Alternating-current-motor controller.



PATENTED JULY 14, 1903.

A. KIMBLE. ALTERNATING CURRENT MOTOR CONTROLLER.

APPLICATION FILED JAN. 26, 1903.

N0 MODEL.

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UNITED STATES Patented J 111y'14, 1903.

PATENT OFFICE.

AUSTIN KIMBLE, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO FRANK S.BETZ, OF CHICAGO, ILLINOIS.

ALTERNATlNG-CURRENT-MOTOR CONTROLLER.

SPECIFICATION forming part of Letters Patent N 0. 733,401, dated July14, 1903.

Application filed January 26,1903. Serial No. 140,630- (No model.)

troller which is particularly adapted for regulating analternating-current motor in which the fields are excited by ashunt-current from the main circuit supplying power for such motor. Iaccomplish this object by the device shown diagrammatically in theaccompanying drawing.

In the construction shown the motor 1 consists of a supporting-frame 2,having an armature 3 journaled therein and having rigidly securedthereto and surrounding said armature an annular series ofradially-disposed cores 4.. The cores 4 are divided into two equalgroups, the members of each group being connected by a pole-piece 5. Thearmature-circuits of the motor 1 are represented by the commutator 6 andthe brushes 7 and 8. Power is supplied to the motor from a main circuitcarrying an alternating current and represented by the conductors 9 and10.

The transformer 11 serves the purpose of varying the voltage of thecurrent supplied to the armature-circuit of the motor 1. Thefield-circuit 12 of the motor 1 is connected by means of the conductors13 and 14 as a shunt of the main circuit and is therefore unchanged bythe action of the transformer.

The controller-lever 15 is pivoted at 16 and is movable so as to comeinto electrical contact with a series of contact-pieces 17 and 18. Thesecondary winding of the transformer 11 consists of a plurality of coils19, connected in series and having their junctions 20 each respectivelyin electrical connection with one of the contact-pieces 17. Theconductor 21 connects the end 22 of the secondary winding of thetransformer with the brush 7 of the motor.

The brush 8 of the motor is connected by means of the conductor 23 withthe controller-lever 15. The contact-piece 18 is connected directly withthe conductor 10 of the main circuit. The primary coil 24. of thetransformer 11 is connected at one end with the conductor 9, and itsother end terminates in a contact-piece 25. A second contact-piece 26,adjacent to but insulated from the contact-piece 25, is connected withthe conductor 50 10. The controller-lever 15 has rigidly secured theretoand insulated therefrom an arm 27, which is suitably arranged to make anelectrical connection between the contactpieces 25 and 26 when the lever15 is in contact with any of the contact-pieces 17 and to break suchconnection when said lever is in contact with either the off button 28or the contact-piece 18. The arm 27 and the contact-pieces 25 and 26thus form a switch controlling the primary circuit 24. A conductor 29connects the conductor 9 with the brush 7 of the motor, but the circuittherein is normally broken at the contact-pieces 30, which are insulatedfrom each other. The 7 lever 15 has also secured thereto and insulatedtherefrom an arm 31, which is suitably located'and is adapted to make anelectrical connection between the contact-pieces 30 when the lever 15 isin connection with the contact-piece 18. The switch 32 controls thepassage of current through the entire system.

To operate the device shown, the switch 32 is thrown in, and a currentis thereby caused to pass through the field-circuit 12 of the motor 1.The lever 15 is then moved in the direction of the small arrow to one ofthe contact-pieces 17, depending upon the desired voltage of thesecondary current. As soon as the lever 15 arrives at one of thecontact- 0 pieces 17 the arm 27 connects the contactpieces 25 and26,completing a circuit and cansing current to pass through the primarycoils 24. The lever 15 having completed the secondary circuit a currentis induced therein 5 motor thus receives its current directly from themain circuit. 1

It will be noticed that the form of controller which is herein describedis particularly useful in connection with the type of motor shown,wherein the speed of the armatureshaft is independent of the frequencyof the current supplied and dependent only upon the voltage in thearmature-circuit and the load on the motor.

. It willbe seen that numerous details of the construction shown may bealtered without departing from the spirit of .my invention. I thereforedo not confine myself to such details except as hereinafter limited inthe claims.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The combinationof a motor; a transformer having primary and secondarycoils of wire on same; a main circuit connected with said primary coil;a field-exciting circuit on said motor connected as a shunt from saidmain circuit; an armatn re-circuit in said motor; a switch adapted toconnect said armature-circuit with the secondary coil of saidtransformer; and means for cutting out said transformer andsimultaneously connecting said armature-circuit directly with said maincircuit, substantially as described.

2. The combination of a motor; a main circuit for supplying power tosaid'motor; a transformer; a primary coil on said trans- I formerconnected with said main circuit; a

switch for controlling said primary coil; a shunt from said main circuitfor exciting the field of said motor; an armature-circuit in said motor;a secondary circuit in said transformer comprising a plurality of coilsconnected in series, one end of said secondary circuit being connectedwith a terminal of said armature-circuit; a series of contactpieces eachconnected with the end of one of said secondary coils; a memberconnected with the remaining terminal of said armaturecircuit andmovable along said series of contact-pieces; an additionalcontact-piece, not connected with said secondary coils, and meansoperated by said member whereby, when said member is in electricalconnection with said additional contact-piece, said primary circuitwillbe broken and said armature-circuit will be excited directly by saidmain circuit, substantially as described.

3. The combination of a motor; a transformer having primary andsecondary coils of wire on same; a main circuit connected with saidprimary coil; afield-exciting circuit on said motor, connected as ashunt from said main circuit; an armature-circuit in said motor havingthe brushes 7 and 8; a lever movably mounted near said transformer-andhaving rigidly secured thereto and insulated therefrom the arms 27 and31; a plurality of contact-pieces 17 adapted to be engaged by the lever15 forjcompleting and regulating the length of the secondary circuit insaid transformer; an additional contact-piece 18 connected with theconductor 10 of said main circuit; the contact-pieces and 26, insulatedfrom each other and adapted to coact with said arm 27 to form a switchfor controlling the primary circuit of said transformer, saidcontact-pieces and arm being arranged to complete the primary circuitwhen the lever 15 is on any of the contact-pieces 17 and to break saidprimary circuit when said lever is moved out of contact with saidcontact-pieces; contact-pieces 3O insulated from each other and adaptedto be engaged by the arm when the lever 15 is in contact with thecontact-piece 18, said contact-pieces 30 being respectively connectedwith the conductor 9 and the brush 7; and a conductor connecting thebrush 8 with the lever 15, substantially as and for the purposespecified.

Signed at Chicago this 23d day of January, 1903.

AUSTIN KIMBLE.

Witnesses:

RUDoW RUMMLER, EUGENE A. RUMMLER.

